Method and Device for Detecting Fault of Signal Processing Equipment and Optical Interface Board Online

ABSTRACT

The disclosure relates to a method and device for detecting a fault of signal processing equipment and an optical interface board on line. The signal processing equipment includes n function modules F 1 , F 2 , . . . Fn, and n fault detecting points T 1 , T 2 , . . . Tn for determining whether there is a fault in said n function modules, wherein n is a natural number. When the detecting result of said detecting point Ti indicates there is a fault in the function module Fi, the corresponding detecting points of other function modules directly associated with the function module Fi are detected continuously, and the reason of the fault is determined according to all the fault function modules. The present disclosure divides the equipment or the board into different modules in accordance with functions, a fault detecting point being set in each module. Therefore, the fault source point of the equipment or the board can be detected and located quickly without artificial participation, and the self-detection can be done automatically when the board is idle to detect problems promptly, so as to improve the testability and the on-site maintainability of products.

TECHNICAL FIELD

The disclosure relates to the field of telecommunications, and inparticular to a method and a device for detecting a fault of signalprocessing equipment and an optical interface board on line,specifically to a Built-In Test (BIT) method of an optical interfaceboard in the equipment with optical Synchronous Digital Hierarchy (SDH).

BACKGROUND

As a fault of the optical network equipment may be occurred during theoperation process, the rapid and effective fault location is veryimportant for the customer and for improving the quality of theequipment. The most conventional fault location method is to inquire therunning state of the board and make an alarm. In order to monitor therunning state of the board, the support of the network management systemis needed; when working abnormally, the board reports the fault to thenetwork management system; then the network management system displaysand alarms the maintainer. The relationship between the networkmanagement system and the SDH network element is shown by FIG. 1,wherein the SDH network element includes an optical interface board andother boards, and is controlled by a network element control board; thenetwork manager monitors the running state of the SDH network element ona display of a server.

However, the network management system is only responsible for reportingand displaying the alarm of the fault rather than processing andanalyzing the fault flexibly. That is to say, the specific fault sourcecannot be located automatically; the regular fault location steps are todetermine gradually by workers and finally determine the fault sourcepoint by means of some loopbacks. Such artificial location method notonly has slow speed, but sometime is also limited by the networkmanagement operating commands. The operable means and methods arelimited; in particular, some location methods can only be finished byprofessionals. Therefore, troubles are made for the in-time faultlocation. Actually, the diagnosis process of the fault can be completelyand automatically finished by the board without the artificialintervention. Here, it is called on-line fault diagnosis system whichfinishes the gradual fault determination on line through the boardsoftware and finally realizes the fault rapid detection and locationfunctions, thereby bringing great convenience for the location of thefault. Besides the fault source point can be detected and located whenthe fault occurs, another advantage of such system is that theself-detection can be done automatically when the board is idle todetect problems promptly and isolate the fault point, so as to improvethe testability and the on-site maintainability of products.

The emphasis of the method and the device for diagnosing the fault ofthe communication apparatus in relating technologies is to classify thefaults, draw an alarm related chart; and finally the artificialoperation is needed to analyze and locate the fault based on thecontrast of the practical alarm and the alarm related chart.

There is another method for diagnosing a fault of a mobile communicationterminal in the relating technologies, the emphasis of which is torecord the condition of the occurrence in real time, but finally analyzethe fault journal artificially.

There is a further method and device for self-diagnosing a fault in therelating technologies; the diagnosis system thereof needs a greatdatabase and a fault correlation analysis module, both of which cannotbe integrated with the board software independently. In addition, theimplementation is to diagnose the fault of the existing equipment, andsuch diagnosis has been limited by the alarm output state of the runningequipment. If the design of the board has not considered the outputtingof enough state information, the use of such method is also limited.Finally, the analysis can be done only when the equipment provide plentyof standard alarm information which has correlation; therefore, thefault location capability is limited.

SUMMARY

The purpose of this disclosure is to provide a method for on-linedetecting a fault of signal processing equipment and an opticalinterface board, which can detect and locate the fault automatically sothat the running condition of the board can be mastered in real time.

This disclosure discloses a method for on-line detecting a fault ofsignal processing equipment. The signal processing equipment includes nfunction modules F1, F2, . . . Fn, and n fault detecting points T1, T2,. . . Tn for determining whether there is a fault in said n functionmodules, wherein n is a natural number. The method comprises thefollows: detecting the fault detection points one by one; when thedetection result of a detection point Ti indicates there is a fault inthe function module Fi, performing the detection on a correspondingdetecting point of other function module directly associated with thefunction module Fi; finding all the function modules with fault; andending the detection, wherein i is any natural number from 1 to n.

In the method for detecting, the step of detecting the fault detectionpoints one by one may comprise the follows: detecting the faultdetection point Tn firstly, wherein the fault detection point Tn is adetection point of the n fault detection points which has a greatestcorrelation with the faults of other function modules; if the detectionresult indicates there is no fault in the function module Fn, indicatingthat all the function modules of the signal processing equipment have nofault.

When the detection result of the detection point Ti indicates there is afault in the function module Fi, the step of performing the detection onthe corresponding detection points of the other function module directlyassociated with the function module Fi may comprise the follows: whenthe serial numbers of n function modules are associated with a streamdirection of a signal and the signal in a function module Fi-1 flows tothe function module Fi, performing the detection on a fault detectionpoint Ti-1 of a function module Fi-1 if the detection result of thedetection point Ti indicates there is a fault in the function module Fi.

The signal processing equipment may be an optical interface board inoptical synchronous digital hierarchy equipment.

This disclosure further discloses a method for on-line detecting a faultof an optical interface board. The optical interface board includes anoptical module F1 and a fault detection point T1 thereof, a clock moduleF2 and a fault detection point T2 thereof, a multiplexing andde-multiplexing module F3 and a fault detection point T3 thereof, aservice processing module F4 and a fault detection point T4 thereof; andthe method comprises the follows:

detecting the fault detection point T4 of the service processing moduleF4 firstly; if there is no fault, indicating that the optical interfaceboard has no fault and ending the detection;

if the detection for the fault detection point T4 indicates there is afault in the service processing module F4, performing the detection onthe fault detection point T3 of the multiplexing and de-multiplexingmodule F3; if there is no fault detected at T3, indicating that thefault is only in the service processing module F4 of the opticalinterface board; and ending the detection;

if the detection of the fault detection point T3 indicates there is afault in the multiplexing and de-multiplexing module F3, performing thedetection on the fault detection point T2; if there is a fault detectedat T2, indicating that there is a fault in the clock module F2 of theoptical interface board or there is a fault in the clock module F2, themultiplexing and de-multiplexing module F3 and the service processingmodule F4 of the optical interface board; and ending the detection;

if the detection of the fault detection point T2 indicates there is nofault in the clock module F2, performing the detection on the faultdetection point T1; if there is no fault detected at T1, indicating thatthere is a fault in the multiplexing and de-multiplexing module F3 ofthe optical interface board; if there is a fault detected at T1,indicating that the fault of the optical interface board comes from theoptical module F1 or an upper stream; and ending the detection; and

if the detection of the fault detection points T2 and T3 indicates thereis a fault in the clock module F2 and there is no fault in themultiplexing and de-multiplexing module F3, performing the detection onthe fault detection point T1; if there is no fault detected at T1,indicating that there is a fault in the service processing module F4 andthe multiplexing and de-multiplexing module F2 of the optical interfaceboard; if there is a fault detected at T1, indicating that the fault ofthe optical interface board comes from the upper stream; and ending thedetection.

The disclosure further discloses a device for on-line detecting a faultof signal processing equipment. The signal processing equipment includesn function modules F1, F2, . . . Fn, and n fault detecting points T1,T2, . . . Tn for determining whether there is a fault in said n functionmodules, wherein n is a natural number. The device comprises:

a fault detection module configured to acquire a state of the faultdetection point in the signal processing equipment;

a fault determination module configured to: determine whether there is afault in a corresponding function module based on the state of the faultdetection point; and a detection management module configured to:control the detection module and the fault determination module; whenthe fault determination module indicates there is a fault in a functionmodule Fi, control the fault detection module to carry on acquiring astate of a corresponding detection point of other function moduledirectly associated with the function module Fi and send the state tothe fault determination module for the determination until all thefunction modules with fault are detected and the fault reasons aredetermined.

The detection management module may be further configured to: select afault detection point Tn in the n fault detection points which has agreatest correlation with the faults of other function modules; controlthe fault detection module and the fault determination module to firstlydetect the fault detection point Tn having greatest correlation with thefault; if the fault determination module determines there is no fault inthe corresponding function module Fn, determine that there is no faultin all the function modules of the signal processing equipment; and endthe detection.

When the serial numbers of the n function modules are associated with astream direction of the signal and the signal in a function module Fi-1flows to the function module Fi, and if the fault determination moduledetermines the state of the fault detection point Ti acquired by thefault detection module to indicate there is a fault in the functionmodule Fi, the detection management module is configured to control thefault detection module and the fault determination module to perform thedetection on the function module Fi-1 until all the function moduleswith the fault has been detected.

The device for detecting is a component of the signal processingequipment.

The method for on-line detecting the fault of the signal processingequipment and the optical interface board disclosed by this disclosureis to divide the equipment or the board into different modules inaccordance with the function; each module is provided with correspondingfault detection point; the fault source point of the equipment or theboard can be detected and located rapidly without artificialparticipation; and self-detection can be done automatically when theboard is idle to detect problems promptly, so as to improve thetestability and the on-site maintainability of products. The device forautomatically on-line diagnosing a fault disclosed by this disclosure isan independent software detection module which can be integrated withthe software module at normal state of the board, and the detection isperformed by an operating system and is easy to realize.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic diagram of a relationship between an SDHnetwork element and a network management system;

FIG. 2 shows a schematic diagram of the correlation between functionmodules and fault detection points of the disclosure;

FIG. 3 shows a flowchart of a method for determining a fault sourcepoint by a software detection module;

FIG. 4 shows a schematic diagram of a working principle of an opticalinterface board in an optical communication system;

FIG. 5 shows a block diagram of function modules and fault detectionpoints of an optical interface board for the alarm correlation analysis;and

FIG. 6 shows a structural diagram of an on-line fault detection deviceof this disclosure.

DETAILED DESCRIPTION

A further detailed description is made for the disclosure by combiningwith the following figures and specific implementation ways.

The disclosure includes three parts as follows: analysis andestablishment of board alarm correlation, establishment of a faultdictionary, and establishment of a detection software module.

Firstly, analysis and establishment of board alarm correlation includesthat: dividing the board at the designing stage into different modulesin accordance with functions, wherein each module should have arespective fault detection point. The module division needs to beaccording to certain basis; that is to say, there is a certain logicrelationship between a function module and a fault detection point,between two function modules or between two fault detection points. Forexample, if the fault detection point Ti depends on the function moduleFi, there is a fault in the function module Fi when the test result ofthe fault detection point Ti is abnormal. In contrast, if the faultdetection point Ti passes through the detection, it proves that thefunction module Fi is normal, that is say, the fault detection point Tiis associated with the function module Fi. Meanwhile, the functionmodule Fi+1 also depends on the function module Fi, and if the detectionpoint Ti of the function module Fi is abnormal, it is possible to detectthat the detection point Ti+1 of the function module Fi+1 is abnormal,which indicates the function module Fi is associated with the functionmodule Fi+1. Finally, providing that only one function module hasproblem at the same moment, said method can be used for diagnosing theproblems one by one when there are problems in multiple function modulesat the same time.

The division of the module may be on basis of the stream direction ofthe signal of the signal processing equipment.

The relationship between the function module and the detection point isshown in FIG. 2; the function module F1, the function module F2 and thefunction module F3 are connected in sequence; the detection point of thefunction module F1 is T1; the detection point of the function module F2is T2; and the detection point of the function module F3 is T3.

Secondly, establishing the fault dictionary based on the result of thealarm correlation analysis, wherein a function module Fi is set as alengthwise coordinate and a fault detection point Ti is set as atransverse coordinate so as to form a two-dimensional matrix. All therows in each column are added so that a fault correlation R can beobtained; the preferential detection point is the one with maximum valueof the fault correlation R; during the establishment of the faultdictionary, in order to bring convenience for the following writing of afault detection software, the serial number of the modules can beadjusted suitably so that the function module with greatest serialnumber corresponds to the item with the maximum value of the faultcorrelation R; thus, in the process for determining the preferablydetected detection point, the detection point of the function modulewith greatest serial number is the preferential detection point. Ifthere is no fault at the preferential detection point, there is no faultin the whole board.

Thirdly, perfecting board software based on the fault dictionary byestablishing a software detection module, wherein different task modulesof the board software structure are called by adopting an operatingsystem, the software detection module is performed at the idle state ofeach level of CPU and is a task module with lowest priority. The workingprocess of the software detection module is as follows: when there is afaulted Ti in the current level Fi, checking the fault detection pointTi-1 of the former level Fi-1 firstly; if there is no fault, indicatingthat the fault is at the current Fi; if there is a fault, checking thefault detection point Ti-2 of the Fi-2 level, and so forth, finallyfinding the source of the fault. The flowchart of the method forspecifically determining the fault source by the software detectionmodule is shown in FIG. 3.

FIG. 4 is a block diagram of a working principle of a service stream ofan optical interface board in an optical communication system; thesignal entering into the optical board is firstly subjected from thephotoelectric conversion by an optical module to get a serial high-speedelectric signal; the serial high-speed electric signal is decomposedinto multiple paths of a low-speed parallel signal by a multiplexing andde-multiplexing module; then the signal are sent to the serviceprocessing module for the corresponding process and finally theprocessed service is sent to other function boards through a servicebus. Similarly, the services from the other function boards through theservice bus and after the detection and other processes by the serviceprocessing module are sent into the multiplexing and de-multiplexingmodule in parallel, and then are input into the optical module after theparallel-series conversion so as to output the optical signals after theelectro-optical conversion. The clock supply module provides a clocksignal to the multiplexing and de-multiplexing module. The detectionpoint in the optical interface board shown in FIG. 4 includes inputoptical signal detection, receiving clock detection, transmitting clockdetection and output optical signal detection.

The optical interface board shown in FIG. 4 is divided into four partsin accordance with the functions: an optical module F1, a clock moduleF2, a multiplexing and de-multiplexing module F3, and a serviceprocessing module F4; the correspondingly detection points arerespectively T1, T2, T3 and T4; and FIG. 5 shows the block diagram ofthe function module and the fault detection point used for the alarmcorrelation analysis on the optical interface board.

In accordance with the division result of the function modules, if afault source point of the board is to be detected due to Loss Of Frame(LOF), for the fault detection point T1 of the optical module F1, itsdetection result is that the input optical power exceeds the threshold(the input optical power is higher than the maximum threshold); for thefault detection point T2 of the clock module F2, its detection result isPLL (Phase-Locked Loop) loss of lock; for the fault detection point T3for the multiplexing and de-multiplexing module F3, its detection resultis that the receiving clock is unlocked; for the fault detection pointT4 of the service processing module F4, its detection result is LOF. Ifa fault source point is to be detected due to Loss Of Signal (LOS), forthe fault detection point T1 of the optical module F1, its detectionresult is LOS of the optical module; for the fault detection point T2 ofthe clock module F2, its detection result is the loss of the clock forthe phase-locked loop; for the fault detection point T3 of themultiplexing and de-multiplexing module F3, its detection result is LOSof multiplexer; for the fault detection point T4 of the serviceprocessing module F4, its detection result is LOS of the service.

The fault dictionary established according to the result of saidcorrelation analysis is as follows:

Function modules and detection points T1 T2 T3 T4 F1 1 0 1 1 F2 0 1 1 1F3 0 0 1 1 F4 0 0 0 1 Fault correlation R 1 1 3 4

The descriptions of 1 and 0 in the table above are as follows: if thereis a fault in F1, it will detect a fault at each detection point of T1,T3 and T4, their corresponding coordinates are 1, and there is no faultat T2 and its corresponding coordinate is 0; if there is a fault in F2,there is no fault at T1, and there will detect a fault at each detectionpoint of T2, T3 and T4, and thus the coordinate of the F2 correspondingto T1 is 0, and the coordinates of the F2 corresponding to T2, T3 and T4are 1; if there is a fault only in F3, there is no fault detected at T1and T2, and there will detect a fault only at detection points T3 andT4; if there is a fault in F4, there is no fault detected at T1, T2 andT3, and there will detect a fault at T4.

The determination of the preferential detection point is as follows:adding all rows in each corresponding column of said table to obtain thefault correlation R; regarding the point with the maximum R as thepreferential detection point; for example, if the addition result of thefirst column is 1, the addition result of the second column is 1, theaddition result of the third column is 3, and the addition result of thefourth column is 4, then the T4 is selected as the preferentialdetection point (namely the first detection point) according to thestrongest correlation with other function modules, that is to say,according to the principle with biggest fault occurrence possibility.The software module writes the software detection module based on thefault dictionary in such way: only detecting T4 by a detection modulewhen the fault detection is started; if there is no fault detected atT4, indicating that there is no fault in the four function modules onthe service stream of the whole unit; once there is a fault detected atT4, indicating there is a fault at F4 or there is a fault possibly in F2and F3 associated with F4; thus, detecting whether there is a fault atT3 firstly; if not, indicating that that there is no fault in F2 as F2provides a clock signal to F3 and F4, and indicating there is a faultonly in F4; in contrast, if there is a fault at T3, detecting T as thefault of F2 will be brought to both F3 and F4, if there is a faultdetected at T2, indicating there is a fault in F2; if there is no faultat T2, detecting F1; if there is a fault detected at T1, indicating thatthe fault is possibly from F1 or the upper stream; in contrast, if thereis not a fault detected at T1, indicating there is a fault in F3.

FIG. 6 is the structural diagram of the on-line fault detection deviceof the disclosure, the device comprises:

a fault detection module 601 configured to acquire a state of the faultdetection point in the signal processing equipment;

a fault determination module 602 configured to determine whether thereis a fault in a corresponding function module based on the state of thefault detection point; and

a detection management module 603 configured to: control the detectionmodule 601 and the fault determination module 602; when the faultdetermination module 602 indicates there is a fault in a function moduleFi, control the fault detection module 601 to carry on acquiring a stateof a corresponding detection point of other function module directlyassociated with the function module Fi and send the state to the faultdetermination module 602 for the determination until all the functionmodules with fault are detected and the fault reasons are determined.

The detection management module 603 is further configured to: select afault detection point Tn in the n fault detection points which has agreatest correlation with the faults of other function modules; controlthe fault detection module 601 and the fault determination module 602 tofirstly detect the fault detection point Tn having greatest correlationwith the fault; if the fault determination module 602 determines thereis no fault in the corresponding function module Fn, determine thatthere is no fault in all the function modules of the signal processingequipment; and end the detection.

When the serial numbers of the n function modules are associated with astream direction of the signal and the signal in a function module Fi-1flows to the function module Fi, and if the fault determination module602 determines the state of the fault detection point Ti acquired by thefault detection module 601 to indicate there is a fault in the functionmodule Fi, the detection management module 603 is configured to controlthe fault detection module and the fault determination module to performthe detection on the function module Fi-1 until all the function moduleswith the fault has been detected.

The device for detecting is a component of the signal processingequipment.

As mentioned above, the method can detect and locate the fault sourcepoint rapidly without artificial participation and carry outself-detection automatically when the board is idle to detect faultspromptly and isolate the fault point, so as to improve the testabilityand the on-site maintainability of products.

INDUSTRIAL APPLICABILITY

The method for on-line detecting a fault of the signal processingequipment and the optical interface board disclosed by this disclosureis to divide the equipment or the board into different modules inaccordance with the function; each module is provided with correspondingfault detection point; the fault source point of the equipment or theboard can be detected and located rapidly without artificialparticipation; and self-detection can be done automatically when theboard is idle to detect problems promptly, so as to improve thetestability and the on-site maintainability of products. The device forautomatically on-line diagnosing a fault disclosed by this disclosure isan independent software detection module which can be integrated withthe software module at normal state of the board, and the detection isperformed by an operating system and is easy to realize.

1. A method for on-line detecting a fault of signal processingequipment, the signal processing equipment comprising n function modulesF1, F2, . . . Fn, and n fault detecting points T1, T2, . . . Tn fordetermining whether there is a fault in said n function modules, whereinn is a natural number; and the method comprising: detecting the faultdetection points one by one; when the detection result of a detectionpoint Ti indicates there is a fault in a function module Fi, performingthe detection on a corresponding detecting point of other functionmodule directly associated with the function module Fi, wherein i is anynatural number from 1 to n; and finding all the function modules withfault, and ending the detection.
 2. The method for detecting accordingto claim 1, wherein the step of detecting the fault detection points oneby one comprises the follows: detecting a fault detection point Tnfirstly, wherein the fault detection point Tn is a detection point ofthe n fault detection points which has a greatest correlation with thefaults of other function modules; if the detection result indicatesthere is no fault in the function module Fn, indicating that all thefunction modules of the signal processing equipment have no fault. 3.The method for detecting according to claim 2, wherein when thedetection result of the detection point Ti indicates there is a fault inthe function module Fi, the step of performing the detection on thecorresponding detection point of other function module directlyassociated with the function module Fi comprises the follows: when theserial numbers of n function modules are associated with a streamdirection of a signal and the signal in a function module Fi-1 flows tothe function module Fi, performing the detection on a fault detectionpoint Ti-1 of a function module Fi-1 if the detection result of thedetection point Ti indicates there is a fault in the function module Fi.4. The method for detecting according to claim 3, wherein the signalprocessing equipment is an optical interface board in opticalsynchronous digital hierarchy equipment.
 5. A method for on-linedetecting a fault of an optical interface board, the optical interfaceboard comprising an optical module F1 and a fault detection point T1thereof, a clock module F2 and a fault detection point F2 thereof, amultiplexing and de-multiplexing module F3 and a fault detection pointT3 thereof, a service processing module F4 and a fault detection pointF4 thereof; and the method comprising: detecting the fault detectionpoint T4 of the service processing module F4 firstly; if there is nofault, indicating that the optical interface board has no fault andending the detection; if the detection for the fault detection point T4indicates there is a fault in the service processing module F4,performing the detection on the fault detection point T3 of themultiplexing and de-multiplexing module F3; if there is no faultdetected at T3, indicating that the fault is only in the serviceprocessing module F4 of the optical interface board; and ending thedetection; if the detection of the fault detection point T3 indicatesthere is a fault in the multiplexing and de-multiplexing module F3,performing the detection on the fault detection point T2; if there is afault detected at T2, indicating that there is a fault in the clockmodule F2 of the optical interface board or there is a fault in theclock module F2, the multiplexing and de-multiplexing module F3 and theservice processing module F4 of the optical interface board; and endingthe detection; if the detection of the fault detection point T2indicates there is no fault in the clock module F2, performing thedetection on the fault detection point T1; if there is no fault detectedat T1, indicating that there is a fault in the multiplexing andde-multiplexing module F3 of the optical interface board; if there is afault detected at T1, indicating that the fault of the optical interfaceboard comes from the optical module F1 or an upper stream; and endingthe detection; if the detection of the fault detection points T2 and T3indicates there is a fault in the clock module F2 and there is no faultin the multiplexing and de-multiplexing module F3, performing thedetection on the fault detection point T1; if there is no fault detectedat T1, indicating that there is a fault in the service processing moduleF4 and the multiplexing and de-multiplexing module F2 of the opticalinterface board; if there is a fault detected at T1, indicating that thefault of the optical interface board comes from the upper stream; andending the detection.
 6. A device for on-line detecting a fault ofsignal processing equipment, the signal processing equipment comprisingn function modules F1, F2, . . . Fn, and n fault detecting points T1,T2, . . . Tn for determining whether there is a fault in said n functionmodules, wherein n is a natural number; and the device comprising: afault detection module configured to acquire a state of the faultdetection point in the signal processing equipment; a faultdetermination module configured to determine whether there is a fault ina corresponding function module based on the state of the faultdetection point; and a detection management module configured to:control the detection module and the fault determination module; whenthe fault determination module indicates there is a fault in a functionmodule Fi, control the fault detection module to carry on acquiring astate of a corresponding detection point of other function moduledirectly associated with the function module Fi and send the state tothe fault determination module for the determination until all thefunction modules with fault are detected and the fault reasons aredetermined.
 7. The device for detecting according to claim 6, whereinthe detection management module is further configured to: select a faultdetection point Tn in the n fault detection points which has a greatestcorrelation with the faults of other function modules; control the faultdetection module and the fault determination module to firstly detectthe fault detection point Tn having greatest correlation with the fault;if the fault determination module determines there is no fault in thecorresponding function module Fn, there is no fault in all the functionmodules of the signal processing equipment; and end the detection. 8.The device for detecting according to claim 7, wherein when the serialnumbers of the n function modules are associated with a stream directionof the signal and the signal in a function module Fi-1 flows to thefunction module Fi, and if the fault determination module determines thestate of the fault detection point Ti acquired by the fault detectionmodule to indicate there is a fault in the function module Fi, thedetection management module is configured to control the fault detectionmodule and the fault determination module to perform the detection onthe function module Fi-1 until all the function modules with the faulthas been detected.
 9. The device for detecting according to claim 7,wherein the device for detecting is a component of the signal processingequipment.